Light-emitting device and manufacturing method thereof

ABSTRACT

This disclosure discloses a method of manufacturing a light-emitting device includes steps of providing a first substrate with a plurality of first light-emitting elements and adhesive units arranged thereon, providing a second substrate with a first group of second light-emitting elements and a second group of second light-emitting elements arranged thereon, and connecting the a second group of second light-emitting elements and the adhesive units. The first light-emitting elements and the first group of second light-emitting elements are partially or wholly overlapped with each other during connecting the second group of second light-emitting elements and the adhesive units.

REFERENCE TO RELATED APPLICATION

This application claims the benefit of Provisional Application Ser. No.62/670,900, filed on May 14, 2018 and Provisional Application Ser. No.62/697,387, filed on Jul. 12, 2018, the content of which is herebyincorporated by reference in its entirety.

BACKGROUND Technical Field

The present disclosure relates to a light-emitting device and itsmanufacturing method, especially to a method of transferring a largenumber of light-emitting elements.

Description of the Related Art

The Light-emitting diodes have been widely used in various applications,such as the pixels in a display and light sources in a backlight module.In the process of manufacturing the display and the backlight module,how to efficiently arrange the numerous light-emitting diodes on thecircuit board of the display or the backlight module is a problem.

SUMMARY OF THE DISCLOSURE

This disclosure discloses a method of manufacturing a light-emittingdevice comprising providing a first substrate, forming a first adhesiveunit on the first substrate, forming a first light-emitting element onthe first substrate, providing a second substrate, forming a secondlight-emitting element on the second substrate, forming a thirdlight-emitting element on the second substrate, and connecting thesecond light-emitting element to the first adhesive unit. The thirdlight-emitting element is overlapped with the first light-emittingelement during connecting the second light-emitting element to the firstadhesive unit.

This disclosure discloses a method of manufacturing a light-emittingdevice comprising providing a first substrate, forming a first adhesiveunit on the first substrate, forming a first light-emitting element onthe first substrate, providing a second substrate comprising anintermediate layer, forming a second light-emitting element on thesecond substrate, forming a first protrusion to push the secondlight-emitting element toward the first substrate and connecting thesecond light-emitting element to the first adhesive unit.

This disclosure discloses method of manufacturing a light-emittingdevice comprising providing a first substrate, forming a first adhesiveunit and a second adhesive unit on the first substrate, forming a firstlight-emitting element on the first substrate, providing a secondsubstrate, forming a second light-emitting element on the secondsubstrate, forming a first protrusion to push the second light-emittingelement toward the first substrate and connecting the secondlight-emitting element to the first adhesive unit and the secondadhesive unit.

BRIEF DESCRIPTION OF THE DRAWING

The accompanying drawings are included to provide easy understanding ofthe application, and are incorporated herein and constitute a part ofthis specification. The drawings illustrate the embodiments of theapplication and, together with the description, serve to illustrate theprinciples of the application.

FIGS. 1A˜1C show schematic views of manufacturing a light-emittingdevice in accordance with one embodiment of the present disclosure.

FIG. 1D shows a schematic view of a light-emitting device in accordancewith one embodiment of the present disclosure.

FIGS. 2A˜2C show schematic views of manufacturing a light-emittingdevice in accordance with one embodiment of the present disclosure.

FIGS. 3A˜3C show schematic views of manufacturing a light-emittingdevice in accordance with one embodiment of the present disclosure.

FIG. 3D shows a schematic view of manufacturing a light-emitting devicein accordance with one embodiment of the present disclosure.

FIGS. 4A˜4G show schematic views of manufacturing a light-emittingdevice in accordance with one embodiment of the present disclosure.

FIGS. 5A˜5G show schematic views of protrusion and adhesive unit inaccordance with one embodiment of the present disclosure.

FIGS. 6A˜6C show schematic views of spacer and substrate in accordancewith one embodiment of the present disclosure.

DETAILED DESCRIPTION OF THE EMBODIMENTS

To better and concisely explain the disclosure, the same name or thesame reference number given or appeared in different paragraphs orfigures along the specification should has the same or equivalentmeanings while it is once defined anywhere of the disclosure.

The following shows the description of embodiments of the presentdisclosure accompanied with the drawings.

FIGS. 1A˜1C show schematic views of manufacturing a light-emittingdevice in accordance with one embodiment of the present disclosure. Thelight-emitting device is, for example, a display using LED chips, LEDpackages, and/or LED CSPs (Chip Scale Package) as pixels, or a backlightmodule using LED chips, LED packages, and/or LED CSPs as light sources.The manufacturing method of this embodiment includes a process that canefficiently transfer a large number of LED chips, LED packages, and/orLED CSPs to the backplane of the display, the backplane of a backlightmodule or a predetermined carrier.

Referring to FIG. 1A, multiple first light-emitting elements 101 arearranged on a first substrate 201 through an intermediate layer 3. To bespecific, the first substrate 201 has a first lower surface 2010 and afirst upper surface 2011, and the first light-emitting elements 101 arearranged on the first lower surface 2010 through the intermediate layer3. In this embodiment, the light-emitting element can be LED chip, LEDpackages, and/or LED CSP. The intermediate layer 3 may continuously orintermittently cover the first lower surface 2010 of the first substrate201. For example, the intermediate layer 3 covers almost or all of thearea of the first lower surface 2010, or covers only the area of thefirst lower surface 2010 corresponding to the first light-emittingelement 101. The first light-emitting element 101 has a substrate (notshown), a p-type semiconductor layer (not shown), an n-typesemiconductor layer (not shown), a light-emitting layer (not shown), afirst electrode pad 120, and a second electrode pad 121. In anembodiment, there is no substrate (for example, growth substrate)included in the first light-emitting element 101. Besides, the firstlight-emitting element 101 has a top surface 1010, a bottom surface 1011opposite to the top surface 1010, and a side surface 1012 arrangedbetween the top surface 1010 and the bottom surface 1011. The topsurface 1010 of the first light-emitting element 101 is connected to theintermediate layer 3. In an embodiment, the bottom surface 1011 is not aflat surface but is a stepped surface composed of a surface of thep-type semiconductor layer, a surface of the n-type semiconductor, and asurface of the light-emitting layer. The first and second electrode pads120, 121 are electrically connected to the p-type semiconductor layerand the n-type semiconductor layer respectively.

Referring to FIG. 1A, the second substrate 202 has a second lowersurface 2021 and a second upper surface 2020 and faces the bottomsurface 1011. There is a plurality of connecting pads 104 disposed onthe second upper surface 2020. The connecting pads 104 are configured toelectrically connect to the first and second electrode pads 120, 121,and to connect the first light-emitting element 101 to power (not shown)and/or the control circuit (not shown). The first light-emittingelements 101 are moved to the second substrate 202 and electricallyconnected to the plurality of connecting pads 104 in the subsequentprocesses shown in FIGS. 1B and 1C.

In an embodiment, the first light-emitting element 101 includes asemiconductor layer including III-V group semiconductor material to emitan incoherent light. The III-V group semiconductor material can beAl_(x)In_(y)Ga_((1-x-y))N or Al_(x)In_(y)Ga_((1-x-y))P, wherein 0≤x,y≤1:(x+y)≤1. The first light-emitting element 101 can emit a red lightwith a peak wavelength or dominant wavelength of 610˜650 nm, emit agreen light with a peak wavelength or dominant wavelength of 495˜570 nm,emit a blue light with a peak wavelength or dominant wavelength of450˜495 nm, emit a purple light with a peak wavelength or dominantwavelength of 400˜440 nm, or emit a UV light with a peak wavelength of200˜400 nm based on different semiconductor materials. In an embodiment,the first light-emitting element 101 has a light-emitting layer and awavelength conversion material arranged on the light-emitting layer. Thewavelength conversion material has one or more of phosphor, quantum dotmaterial, or combinations thereof. The phosphor can be yellow-greenishphosphor, red phosphor, or blue phosphor. The yellow-greenish phosphorincludes YAG, TAG, silicate, vanadate, alkaline-earth metal selenide, ormetal nitride. The red phosphor includes fluoride (K₂TiF₆:Mn⁴⁺,K₂SiF₆:Mn⁴⁺), silicate, vanadate, alkaline-earth metal sulfide,oxynitride, or a mixture of tungstate and molybdate. The blue phosphorincludes BaMgAlioOi₇ Eu²⁺. The quantum dot material can be ZnS, ZnSe,ZnTe, ZnO, CdS, CdSe, CdTe, GaN, GaP, GaSe, GaSb, GaAs, AlN, AlP, AlAs,InP, InAs, Te, PbS, InSb, PbTe, PbSe, SbTe, ZnCdSeS, CuInS, CsPbCl₃,CsPbBr₃, CsPbI₃. In an embodiment, the first light-emitting element 101including a wavelength conversion material can emit a white light,wherein the white light has a color temperature between 10000K and20000K, and has a color point coordinate (x, y) in the CIE 1931chromaticity diagram, wherein 0.27≤x≤0.285; 0.23≤y≤0.26. In oneembodiment, the white light emitted by the first light-emitting element101 has a color temperature between 2200K and 6500K (for example, 2200K,2400K, 2700K, 3000K, 5700K, 6500K) and has a color point coordinate (x,y) located in the 7-step MacAdam ellipse in the CIE1931 chromaticitydiagram.

The first substrate 201 is a substrate configured to carry thelight-emitting elements. In an embodiment, the first substrate 201 is asubstrate that can be entirely or partially restored after beingstretched or being bent, for example, a blue tape. In an embodiment, thefirst substrate 201 is a solid substrate that cannot be recovered afterbeing deformed at room temperature, such as a sapphire substrate. Thesecond substrate 202 is a substrate configured to receive thelight-emitting elements transferred from the first substrate 201. In anembodiment, the second substrate 202 is a PCB (Printed Circuit Board)including conductive material and insulating material. The conductivematerial can be copper, tin, gold or aluminum. The insulating materialcan be epoxy, glass fiber, alumina, aluminum nitride or combinationsthereof. In an embodiment, the connecting pad 104 has titanium,chromium, platinum, copper, nickel, gold, tin or alloys thereof. Theconnecting pad 104 can be single layer or multiple layers. In anembodiment, the second substrate 202 is a backplane of a backlightmodule or a backplane of a display.

Referring to FIG. 1B, multiple adhesive units 5 are arranged to covermore than two connecting pads 104. The adhesive unit 5 includesinsulating material and conductive particles 501 dispersed within. Asshown in FIG. 1B, there are two spacers 61, 62 optionally arrangedbetween the first substrate 201 and the second substrate 202 to keep adistance between the first substrate 201 and the second substrate 202 inorder to avoid the first light-emitting element 101 from directlycontacting the connecting pad 104 or the adhesive unit 5 before beingseparated from the first substrate 201. In an embodiment, the distancebetween the first substrate 201 and the second substrate 202 kept by thespacers 61, 62 is larger than twice of the height of the firstlight-emitting element 101. In another embodiment, the distance betweenthe first substrate 201 and the second substrate 202 can be maintainedby other mechanism so the spacer may be omitted. In an embodiment, thespacers 61, 62 are arranged on edge portions and/or central portions ofthe second substrate 202. In another embodiment, one or more spacers(not shown) are arranged between the spacers 61, 62. In an embodiment,the spacers 61, 62 are formed on the first substrate 201 or on thesecond substrate 202 before transferring the first light-emittingelements 101. The spacers can be arranged to form various patterns onthe substrate, and related descriptions can be referred to FIGS. 6A˜6Cand related paragraphs.

The adhesive unit 5 physically and electrically connects the firstlight-emitting element 101 and the connecting pad 104. The adhesive unit5 includes insulating material and conductive particles 501 dispersedwithin. The conductive particles 501 can be aggregated on the connectingpads 104 and on the first and second electrode pads 120, 121 by heating.The first light-emitting element 101 can be electrically connected tothe connecting pad 104 through the aggregated conductive particles 501within the insulating material of adhesive unit 5. The insulatingmaterial can be silicone, epoxy or the like. The material of theconductive particle 501 can be tin, copper, silver, gold or the like. Tobe more specific, the aggregated conductive particles 501 form aconductive pillar 502 connecting the electrode pads and the connectingpads as shown in FIG. 1D. In the embodiment, the thickness of theadhesive unit 5 after connecting with the first light-emitting element101 is less than 5 μm. In another embodiment, the thickness of theadhesive unit 5 after connecting with the first light-emitting element101 is larger than 3 μm. In further another embodiment, the thickness ofthe adhesive unit 5 after connecting with the first light-emittingelement 101 is between 1 μm and 4 μm. In the embodiments, the adhesiveunit is an ACP (anisotropic conductive paste) or an ACF (anisotropicconductive film).

In an embodiment, the adhesive unit 5 is composed only of insulatingmaterial. A metal structure (not shown) is formed on a surface of thefirst and second electrode pads 120, 121 facing the connecting pad 104.The metal structure can be single layer or multiple layers. The metalstructure is deformed to electrically and physically connect to theconnecting pad 104 and the first and second electrode pads 120, 121after being heated and/or pressed, so the deformed metal structure formsthe electrical connection path between the connecting pad 104 and thefirst and second electrode pads 120, 121. In an embodiment, the metalstructure includes lead, tin, indium, gold or alloys thereof. Before theconnection pad 104 is covered by the adhesive unit 5, the surface of theconnection pad and the surface of the metal structure can be oxidized sothere is oxide formed thereon. When the adhesive unit 5 is flux, theadhesive unit 5 can remove the oxide on the surface of the metalstructure and the oxide on the surface of the connecting pad 104.Therefore, the adhesive unit 5 improves the strength of connectionbetween the metal structure and the connecting pad 104 and facilitatesthe deformation of the metal structure within the adhesive unit 5.

In an embodiment, the adhesive unit 5 includes insulating material andconductive particles. The first and second electrode pads 120, 121 canbe metal and include multiple layers. In an embodiment, the metalincludes lead, tin, indium, gold or alloy thereof. In an embodiment, theoutermost layer of the first and second electrode pads 120, 121 includeslead, tin, indium, gold or alloy thereof. The conductive particles canbe aggregated onto the connecting pads 104 and the first and secondelectrode pads 120, 121 via heat and/or force. Then, the conductiveparticles within the adhesive unit 5 are electrically connected to anddirectly connected to the first and second electrode pads 120, 121 andthe connecting pads 104.

Referring to FIG. 1C, the protrusions 30 is formed on the intermediatelayer 3, and the first light-emitting elements 101 located right beneaththe protrusions 30 are pushed away from the intermediate layer 3. In theembodiment, one protrusion 30 pushes one first light-emitting element101 arranged right beneath the protrusion 30 to the adhesive unit 5. Thefirst light-emitting element 101 is detached from the intermediate layer3 before being in contact with the adhesive units 5 on the secondsubstrate 202. In other words, the first light-emitting elements 101 donot contact with the intermediate layer 3 during moving from the firstsubstrate 201 to the second substrate 202. Besides, the moving distanceof the first light-emitting element 101 after being detached from theintermediate layer 3 is equal to or less than the distance between thefirst substrate 201 and the second substrate 202 minus the height of thefirst light-emitting element 101 and the height of the connecting pads104. In another embodiment, the intermediate layer 3 has a bubble layer(not shown) and an adhesive structure (not shown). The bubble layer isformed between the first substrate 201 and the adhesive structure. Theadhesive structure is connected to the first light-emitting element 101.One or more blisters (not shown) are generated from the bubble layer byheating the bubble layer, so the bubble layer (not shown) and/or theadhesive structure are/is bulged to form the protrusions 30. Asdescribed above, the first light-emitting element 101 pushed to thesecond substrate 202 can be fixed on the second substrate 202 throughthe adhesive unit 5. In another embodiment, one or more protrusions 30can be formed to push one or more first light-emitting elements 101, andrelated descriptions can be referred to FIGS. 5A˜5G and relatedparagraphs. Referring to FIG. 1C, two first light-emitting elements 101pushed from the first substrate 201 to the second substrate 202 arespaced from each other by three first light-emitting elements 101 whilebeing arranged on the first substrate 201. The two first light-emittingelements 101 pushed from the first substrate 201 to the second substrate202 can be spaced from each other by four or more first light-emittingelements 101 or by two or less first light-emitting elements 101. So,the distance between two neighboring first light-emitting elements 101on the second substrate 202 can be decided by the number of the firstlight-emitting elements 101 between two first light-emitting elements101 to be transferred while being arranged on the first substrate 201.

The protrusions 30 are generated by applying laser to the bubble layer.In an embodiment, the laser has a wavelength between 260 nm and 380 nm.For example, the wavelength can be 266 nm, 355 nm, or 375 nm. In anembodiment, the bubble layer is heated to form gas accumulated intoblisters. The blister layer and/or the adhesive structure are bulged toform protrusions. The gas in the blisters does not leak out of theintermediate layer 3. In another embodiment, the first substrate 201 hasa transmittance over 90% or a reflectance less than 10% with respect tothe laser, the laser can pass through the first substrate 201. In anembodiment, the bubble layer includes polyimide.

FIG. 1D shows a schematic view of a light-emitting device in accordancewith one embodiment of the present disclosure. The light-emitting device1000 in FIG. 1D has a first light-emitting element 101, a secondsubstrate 202, and an adhesive unit 5. The first light-emitting element101 is fixed on the second substrate 202 and has the first and secondelectrode pads 120, 121, and the second substrate 202 has connectingpads 104. The adhesive unit 5 contains conductive particles 501, andsome of the conductive particles 501 may be aggregated to form theconductive pillar 502 for electrically connecting the firstlight-emitting element 101 and the connecting pads 104, while the restof the conductive particles 501 are dispersed within adhesive unit 5. Inan embodiment, the pillar 502 has an upper portion 5012 close to thefirst light-emitting element 101, a lower portion 5010 close to thesecond substrate 202, and a neck portion 5011 arranged between the upperportion 5012 and the lower portion 5010. The width of the neck portion5011 is less than the width of the upper portion 5012 or less than thewidth of the lower portion 5010. Some conductive particles 501 aredispersed within the insulating material, but not aggregated on thefirst and second electrode pads 120,121 or on the connecting pad 104.The deformation of the adhesive unit 5 can be performed by heatingand/or pressing. In an embodiment, the adhesive unit 5 covers at least apart of the side surface 1012. When the first light-emitting element 101is detached from the intermediate layer 3, there may be residualsremaining on the first light-emitting element 101. In an embodiment, thesecond substrate 202 includes conductive wires (not shown), activeelectronic elements (not shown) and/or passive electronic elements (notshown) arranged on the second lower surface 2021 and/or the second uppersurface 2020 to control one or multiple first light-emitting elements101. The conductive wires can be metal wires, and the material of themetal wire can be copper, aluminum, or gold. The active electronicelement can be a control chip or a transistor. The passive electronicelement can be a resistor or a capacitor.

FIGS. 2A˜2C show schematic views of manufacturing a light-emittingdevice in accordance with one embodiment of the present disclosure. InFIG. 2A, the second light-emitting elements 102 on the third substrate203 being pushed to the second substrate 202 while the firstlight-emitting elements 101 are connected to the second substrate 202through the adhesive units 5. As shown in the upper part of FIG. 2A, asecond substrate 202 and the first light-emitting elements 101, adhesiveunits 5, and connecting pads 104 arranged on the second substrate 202are provided, the third substrate 203 and the intermediate layer 3 andthe second light-emitting elements 102 arranged on the third substrate203 are provided, and the spacers 61, 62 between the second substrate202 and the third substrate 203 are provided. As shown in the lower partof FIG. 2A, the second light-emitting elements 102 on the secondsubstrate 203 are transferred to the second substrate 202. In otherwords, after arranging the first light emitting elements 101 on thesecond substrate 202 as shown in FIGS. 1A˜1C, a third substrate 203 withsecond light-emitting elements 102 arranged thereon is provided, and allor part of the second light-emitting elements 102 are transferred to thearea of the second substrate 202 not occupied by the firstlight-emitting elements 101. The third substrate 203 has a third lowersurface 2030 and a third upper surface 2031, and the secondlight-emitting elements 102 are arranged on the third lower surface 2030through the intermediate layer 3. To be more specific, the intermediatelayer 3 as discussed above is formed on the third lower surface 2030 ofthe third substrate 203. The protrusions 30 are formed from theintermediate layer 3 to push the second light-emitting elements 102arranged right beneath the protrusions 30 to be directly contacted withthe adhesive units 5. The intermediate layer 3 may continuously orintermittently cover the third lower surface 2030 of the third substrate203. For example, the intermediate layer 3 covers almost or all of thearea of the third lower surface 2030, or covers only the area of thethird lower surface 2030 corresponding to the second light-emittingelement 102. The spacers 61, 62 are arranged between the secondsubstrate 202 and the third substrate 203 to avoid direct contactbetween the second light-emitting element 102 and the firstlight-emitting element 101, between the second light-emitting element102 and the connecting pads 104, or between the second light-emittingelement 102 and the adhesive unit 5 before the process of transferring.The arrangements of the spacers 61, 62 on the second substrate 202 canbe referred to FIGS. 6A˜6C and related paragraphs. In an embodiment, thedistance between the second substrate 202 and the third substrate 203 islarger than the twice of the height of first light-emitting element 101or larger than twice of the height of the second light-emitting element102. The procedure of pushing the second light-emitting elements 102 tothe adhesive units 5 is similar with that of pushing the firstlight-emitting elements 101 to the adhesive units 5, and the relateddescriptions can be referred to previous paragraphs. During pushing thesecond light-emitting elements 102, some of the second light-emittingelements 102 on the third substrate 203 are overlapped with the firstlight-emitting elements 101 transferred to the second substrate 202. Thesecond light-emitting element 102 (i.e, the second light-emittingelements not transferred) which is overlapped with the firstlight-emitting element 101 is not transferred to the second substrate202. The second light-emitting element 102 not transferred can be whollyor partially overlapped with the first light-emitting element 101.Although the first light-emitting elements 101 and some of the secondlight-emitting elements 102 are overlapped with each other, theoverlapped first light-emitting element 101 and the secondlight-emitting element 102 are not directly contacted with each otherbecause the distance between the second substrate 202 and the thirdsubstrate 203 is designed to be larger than the sum of the height of theoverlapped first light-emitting element 101 and the height of the secondlight-emitting element 102 as shown in FIG. 2A. The secondlight-emitting elements 102 are pushed to the second substrate 202 to bebonded to the adhesive units 5 on the second substrate 202 by theprotrusions 30. The adhesive units 5 are formed on the second substrate202 before the second light-emitting elements 102 are pushed to thesecond substrate 202. Alternatively, the adhesive units 5 are formed onthe second substrate 202 before connecting the first light-emittingelements 101 to the second substrate 202. The spacers 61, 62 arearranged between the second substrate 202 and the third substrate 203 toavoid the second light-emitting element 102 from directly contactingwith the first light-emitting element 101, the connecting pad 104 or theadhesive unit 5.

As shown in FIG. 2A, the second light-emitting elements 102 are pushedto the second substrate 202 and to be separated from the third substrate203. The space between the third substrate 203 and the second substrate202 can be controlled to avoid direct contact between the firstlight-emitting element 101 and the second light-emitting element 102.Therefore, the second light-emitting element 102 which is overlappedwith the first light-emitting element 101 is not directly contacted withthe first light-emitting element 101 and can be kept at the sameposition without being removed in advance during pushing the secondlight-emitting elements 102 to the connecting pads 104. Referring toFIG. 2A, a laser is applied to the intermediate layer 3 to form theprotrusions. In an embodiment, the third substrate 203 has atransmittance over 90% or a reflectance less than 10% with respect tothe laser, the laser can pass through the third substrate 203. Thedescriptions about laser can be referred previous paragraphs.

FIG. 2B shows the schematic view of the third light-emitting elements103 on the fourth substrate 204 being pushed to the connecting pads 104on the second substrate 202 to form the light-emitting device 2000 inFIG. 2C while the first light-emitting elements 101 and the secondlight-emitting elements 102 are connected to the second substrate 202through the adhesive units 5. The fourth substrate 204 has a fourthlower surface 2040 and a fourth upper surface 2041, and the thirdlight-emitting elements 103 are arranged on the fourth lower surface2040 through the intermediate layer 3. In other words, FIG. 2B shows thesituation of transferring the third light-emitting elements 103 to thearea of the second substrate 202 not occupied by the firstlight-emitting elements 101 or the second light-emitting elements 102while the first light-emitting elements 101 and the secondlight-emitting elements 102 are arranged on the second substrate 202.The intermediate layer 3 is arranged on the fourth lower surface 2040 ofthe fourth substrate 204, and multiple protrusions 30 are formed to pushthe third light-emitting elements 103 outward from the intermediatelayer 3 to the adhesive units 5. The third light-emitting elements 103are further fixed on the adhesive units 5 by heating the adhesive units5 and/or pressing the third light-emitting elements 103 after connectingthe third light-emitting elements 103 and the adhesive units 5. Thespacers 61, 62 are arranged between the second substrate 202 and thefourth substrate 204 to avoid direct contact between the thirdlight-emitting element 103 and the first and second light-emittingelements 101, 102, direct contact between the third light-emittingelement 103 and the connecting pads 104, and direct contact between thethird light-emitting element 103 and the adhesive unit 5 beforefinishing the process of transferring the third light-emitting elements103. The procedure of pushing the third light-emitting elements 103 tothe adhesive units 5 is similar with that of pushing the firstlight-emitting elements 101 to the adhesive units 5, and the relateddescriptions can be referred to previous paragraphs. The intermediatelayer 3 may continuously or intermittently cover the fourth lowersurface 2040 of the fourth substrate 204. For example, the intermediatelayer 3 covers almost or all of the area of the fourth lower surface2040, or covers only the area of the fourth lower surface 2040corresponding to the third light-emitting element 103. As shown in thelateral view of FIG. 2B, some third light-emitting elements 103 arrangedon the fourth substrate 204 are overlapped with the first light-emittingelements 101 on the second substrate 202, and some third light-emittingelements 103 arranged on the fourth substrate 204 are overlapped withthe second light-emitting elements 102 on the second substrate 202. Thethird light-emitting elements 103 overlapped with the firstlight-emitting elements 101, 102 are not removed during connecting thethird light-emitting elements 103 with the connecting pads 104. Thespace between the fourth substrate 204 and the second substrate 202 islarge enough to avoid direct contact between the first light-emittingelements 101, 102 and the third light-emitting elements 103. In otherwords, the distance between the fourth substrate 204 and the secondsubstrate 202 is larger than the sum of the height of the firstlight-emitting element 101 and the height of the third light-emittingelement 103, and is larger than the sum of the height of the secondlight-emitting element 102 and the height of the third light-emittingelement 103. The overlapped first light-emitting element 101 (or thesecond light-emitting element 102) and the third light-emitting element103 are not directly contacted with each other. As shown in FIG. 2B, theadhesive units 5 are formed on the second substrate 202 before pushingthe third light-emitting elements 103 to the second substrate 202.Furthermore, the adhesive units 5 can be formed on the second substrate202 before connecting the first light-emitting elements 101 with thesecond substrate 202 or before connecting the second light-emittingelements 102 with the second substrate 202. Referring to FIG. 2B, alaser is applied to form the protrusions. In an embodiment, the fourthsubstrate 204 has a transmittance over 90% or a reflectance less than10% with respect to the laser, the laser can pass through the fourthsubstrate 204. The descriptions about laser can be referred previousparagraphs.

Referring to FIG. 2C, the light-emitting device 2000 has firstlight-emitting elements 101, second light-emitting elements 102, thirdlight-emitting elements 103, the second substrate 202, the adhesiveunits 5, and connecting pads 104. In an embodiment, the adhesive units 5arranged between the first, second and third light-emitting elements101, 102, 103 and the second substrate 202 are directly connected to thebottom surface of the light-emitting elements, for example, the bottomsurface 1011. In an embodiment, conductive wires, active electronicelements and passive electronic elements are arranged on the secondlower surface 2021 and/or the second upper surface 2020 of the secondsubstrate 202 to be electrically connected to the connecting pads 104 tocontrol the first light-emitting elements 101, 102, 103. Descriptionsabout the conductive wires, active electronic elements and passiveelectronic elements can be referred to previous paragraphs.

In an embodiment, the first light-emitting element 101, the secondlight-emitting element 102, and the third light-emitting element 103emit lights of different peak wavelengths. For example, the firstlight-emitting element 101 emits a red light with a peak wavelength of610˜650 nm, the second light-emitting element 102 emits a green lightwith a peak wavelength of 495˜570 nm, and the third light-emittingelement 103 emits a blue light with a peak wavelength of 450˜495 nm. Inan embodiment, the light-emitting device 2000 is a display having thefirst light-emitting elements 101, the second light-emitting elements102, and the third light-emitting elements 103 as pixels.

In an embodiment, the light-emitting device 2000 emits a light of asingle color. The first light-emitting elements 101, the secondlight-emitting elements 102, and the third light-emitting elements 103emit lights of same or similar peak wavelengths. For example, the firstlight-emitting elements 101, the second light-emitting elements 102, andthe third light-emitting elements 103 emit blue lights having a peakwavelength between 420 nm and 495 nm. In an embodiment, thelight-emitting device 2000 is a light source for daily lightingapplication, and emits a light having a color temperature between 2200Kand 6500K (for example, 2200K, 2400K, 2700K, 3000K, 5700K, 6500K). In anembodiment, the light-emitting device 2000 is a back light source of aLCD display, and emits a light having a color temperature between 10000Kand 20000K, and has a color point coordinate (x, y) in the CIE 1931chromaticity diagram, 0.27≤x≤0.285; 0.23≤y≤0.26. In order to provide alight of a color, the first light-emitting elements 101, the secondlight-emitting elements 102, and the third light-emitting elements 103can be commonly covered by the same wavelength conversion structure, orthe first light-emitting elements 101, the second light-emittingelements 102, and the third light-emitting elements 103 can berespectively covered by different wavelength conversion structures toconvert light from the first light-emitting elements 101, the secondlight-emitting elements 102, and the third light-emitting elements 103.The wavelength conversion structure includes material to convert thelight, such as the phosphor, quantum dots, or dyes.

FIGS. 3A˜3C show schematic views of manufacturing a light-emittingdevice in accordance with one embodiment of the present disclosure. Asshown in FIG. 3A, a sixth substrate 702 and a fifth substrate 701 havingan intermediate layer 3 formed thereon are provided, and the firstlight-emitting elements 101 are connected to the fifth substrate 701through the intermediate layer 3. Then, the first light-emittingelements 101 are pushed to the sixth substrate 702 by the protrusions30. Descriptions related to the intermediate layer, the light-emittingelement, and the protrusion can be referred to previous paragraphs. Thefirst light-emitting element 101 has a bottom surface 1010 close to thesixth substrate 702 and a top surface 1011 close to the fifth substrate701. The first light-emitting elements 101 are connected to theintermediate layer 3 through the first and second electrode pads 120,121. The fifth substrate 701 has a fifth lower surface 7010 and a fifthupper surface 7011, and the first light-emitting elements 101 arearranged on the fifth lower surface 7010 through the intermediate layer3. The intermediate layer 3 may continuously or intermittently cover thefifth lower surface 7010 of the fifth substrate 701. For example, theintermediate layer 3 covers almost or all of the area of the fifth lowersurface 7010, or covers only the area of the fifth lower surface 7010corresponding to the first light-emitting element 101. The firstlight-emitting elements 101 arranged right beneath the protrusions 30are pushed to the sixth substrate 702 by the protrusions 30. The bottomsurface 1010 is directly connected to the sixth substrate 702. The sixthsubstrate 702 can be adhesive, so the first light-emitting elements 101can be fixed on predetermined positions of the sixth substrate 702. Forexample, the sixth substrate 702 is a blue tape or an UV release tape.Referring to FIG. 3A, a laser is applied to the intermediate layer 3 toform the protrusions. In an embodiment, the fifth substrate 701 has atransmittance over 90% or a reflectance less than 10% with respect tothe laser, the laser can pass through the fifth substrate 701. Thedescriptions about laser can be referred to previous paragraphs. Inembodiment, a spacer is arranged between the fifth substrate 701 and thesixth substrate 702 to prevent direct contact between the firstlight-emitting element 101 and the sixth substrate 702 duringtransferring the first light-emitting elements 101.

FIG. 3B shows the second light-emitting elements 102 on the seventhsubstrate 703 and the third light-emitting elements 103 on the eighthsubstrate 704, and the step of transferring the second light-emittingelements 102 and the third light-emitting elements 103 to the sixthsubstrate 702 by the protrusions 30. To be more specific, the second andthird light-emitting elements 102, 103 are transferred to the sixthsubstrate 702 while the first light-emitting elements 101 are arrangedon the sixth substrate 702. Referring to the upper part of FIG. 3B, asixth substrate 702 and the first light-emitting elements 101 arrangedthereon are provided, and a seventh substrate 703 and multiple secondlight-emitting elements 102 and an intermediate layer 3 arranged thereonare provided. The seventh substrate 703 has a seventh lower surface 7030and a seventh upper surface 7031, an intermediate layer 3 is formed onthe seventh lower surface 7030 of the seventh substrate 703, and thesecond light-emitting elements 102 are arranged on the seventh lowersurface 7030 through the intermediate layer 3. The protrusions 30 pushthe second light-emitting elements 102 to the sixth substrate 702. Theintermediate layer 3 may continuously or intermittently cover theseventh lower surface 7030 of the seventh substrate 703. For example,the intermediate layer 3 covers almost or all of the area of the seventhlower surface 7030, or covers only the area of the seventh lower surface7030 corresponding to the second light-emitting element 102. Referringto the lower part of FIG. 3B, a sixth substrate 702 and the first andsecond light-emitting elements 101, 102 arranged thereon are provided,and an eighth substrate 704 and multiple third light-emitting elements103 and an intermediate layer 3 arranged thereon are provided. Theeighth substrate 704 has an eighth lower surface 7040 and an eighthupper surface 7041, an intermediate layer 3 is formed on the eighthlower surface 7040 of the eighth substrate 704, and the thirdlight-emitting elements 103 are arranged on the eighth lower surface7040 through the intermediate layer 3. The protrusions 30 push the thirdlight-emitting elements 103 to the sixth substrate 702. The intermediatelayer 3 may continuously or intermittently cover the eighth lowersurface 7040 of the eighth substrate 704. For example, the intermediatelayer 3 covers almost or all of the area of the eighth lower surface7040, or covers only the area of the eighth lower surface 7040corresponding to the third light-emitting element 103. The distancebetween the sixth substrate 702 and the seventh substrate 703 is largerthan the sum of the height of the first light-emitting element 101 andthe height of the second light-emitting element 102. The distancebetween the sixth substrate 702 and the eighth substrate 704 is largerthan the sum of the height of the first light-emitting element 101 andthe height of the third light-emitting element 103 or the sum of theheight of the second light-emitting element 102 and the height of thethird light-emitting element 103. Referring to FIG. 3B, a laser isapplied to the intermediate layer 3 on the seventh substrate 703 andanother laser is applied on the intermediate layer 3 on the eighthsubstrate 704 to form the protrusions 30. In an embodiment, each of theseventh substrate 703 and the eighth substrate 704 has a transmittanceover 90% or a reflectance less than 10% with respect to the laser so thelaser can pass through the seventh substrate 703 and the eighthsubstrate 704 respectively. The descriptions about laser can be referredto previous paragraphs.

FIG. 3C shows the step of connecting the first light-emitting elements101, the second light-emitting elements 102, and third light-emittingelements 103 on the sixth substrate 702 to the ninth substrate 705. Asshown in the upper part of FIG. 3C, the first light-emitting elements101, the second light-emitting elements 102, and the thirdlight-emitting elements 103 are arranged on the sixth substrate 702.Next, as shown in the middle part of FIG. 3C, the sixth substrate 702 isflipped upside down, and a ninth substrate 705 having the connectingpads 104 and the adhesive units 5 is placed under the firstlight-emitting elements 101, the second light-emitting elements 102, andthe third light-emitting elements 103. After the sixth substrate 702 isflipped upside down, it moves towards the ninth substrate 705.Alternatively, after the sixth substrate 702 is flipped upside down, itis fixed and the ninth substrate 705 is moved towards the sixthsubstrate 702. Or the sixth substrate 702 and the ninth substrate 705move towards each other. Either way, the first light-emitting elements101, the second light-emitting elements 102, and third light-emittingelements 103 are moved toward the ninth substrate 705 before beingconnected to the adhesive units 5. Then, the first light-emittingelements 101, the second light-emitting elements 102, and thirdlight-emitting elements 103 are fixed to the adhesive units 5 by heatingthe adhesive units 5 and/or pressing the sixth substrate 702. Then, asshown in the lower part of FIG. 3C, the sixth substrate 702 is removedto form the light-emitting device 3000. The light-emitting device 3000has the first light-emitting elements 101, the second light-emittingelements 102, the third light-emitting elements 103, the ninth substrate705, the adhesive units 5 and connecting pads 104. The light-emittingdevice 3000 can be a display or a backlight module. The descriptionabout the adhesive unit can be referred to previous paragraphs, and isomitted for brevity.

Except the manufacturing process disclosed in FIGS. 3A˜3C, thelight-emitting elements can be moved to a substrate having anintermediate layer arranged thereon before being connected to asubstrate having adhesive units and connecting pads arranged thereon toform the light-emitting device 3000. To be more specific, referring toFIG. 3D, the first light-emitting elements 101, the secondlight-emitting elements 102, and the third light-emitting elements 103are transferred to a sixth substrate 702 having an intermediate layer 3formed thereon. The sixth substrate 702 has a sixth lower surface 7021and a sixth upper surface 7020. The first light-emitting elements 101,the second light-emitting elements 102, and the third light-emittingelements 103 are arranged on the sixth upper surface 7020 through theintermediate layer 3. Then, a ninth substrate 705 having connecting pads104 and adhesive units 5 arranged thereon is provided. The ninthsubstrate 705 has a ninth lower surface 7051 and a ninth upper surface7050. The connecting pads 104 and adhesive units 5 are arranged on theninth upper surface 7050. The sixth substrate 702 is turned over, andthe first light-emitting elements 101, the second light-emittingelements 102, and the third light-emitting elements 103 are pushedtoward the ninth substrate 705. Multiple protrusions 30 are formed onthe intermediate layer 3. The first light-emitting elements 101, thesecond light-emitting elements 102, and the third light-emittingelements 103 are pushed to the ninth substrate 705 by the protrusions30, and the first light-emitting elements 101, the second light-emittingelements 102, and the third light-emitting elements 103 are fixed on theadhesive units 5 by heating the adhesive units 5 and/or pressing thefirst light-emitting elements 101, the second light-emitting elements102, and the third light-emitting elements 103. The sixth substrate 702is then removed to form the light-emitting device 3000. Referring toFIG. 3D, a laser is applied to the intermediate layer 3 to form theprotrusions 30. In an embodiment, the sixth substrate 702 has atransmittance over 90% or a reflectance less than 10% with respect tothe laser so the laser can pass through the sixth substrate 702. Thedescriptions about laser can be referred previous paragraphs. Inembodiment, conductive wires, active electronic elements and/or passiveelectronic elements are arranged on the ninth lower surface 7051 and/orthe ninth upper surface 7050 of the ninth substrate 705. Descriptionsabout the conductive wires, active electronic elements and passiveelectronic elements can be referred to previous paragraphs. In anembodiment, referring to the step shown in FIGS. 3C and 3D, a spacer isarranged between the sixth substrate 702 and the ninth substrate 705.The spacer is provided to keep the distance between the sixth substrate702 and the ninth substrate 705, so as to prevent the firstlight-emitting elements 101, the second light-emitting elements 102, andthe third light-emitting elements 103 from directly contacting theadhesive units 5 or the ninth substrate 705 before being detached fromthe sixth substrate 702. Descriptions about the spacer can be referredto previous paragraphs.

FIGS. 4A˜4G show schematic views of manufacturing a light-emittingdevice in accordance with one embodiment of the present disclosure. Asshown in FIG. 4A, a tenth substrate 901 carrying multiple firstlight-emitting elements 101 and an eleventh substrate 902 are provided.The tenth substrate 901 is connected to the eleventh substrate 902through the adhesive structure 50. The first light-emitting element 101is surrounded by the adhesive structure 50. Description about the firstlight-emitting element 101 can be referred to previous paragraphs. Theadhesive structure 50 physically fixes the tenth substrate 901 to theeleventh substrate 902. In an embodiment, the adhesive structure 50includes an insulating material such as silicone or epoxy. The firstlight-emitting element 101 has a top surface 1010 facing the tenthsubstrate 901, a bottom surface 1011 facing the eleventh substrate 902,and a side surface 1012 connecting the top surface 1010 and the bottomsurface 1011. In an embodiment, the bottom surface 1011 is directlycontacted with the adhesive structure 50. In an embodiment, the tenthsubstrate 901 is a substrate for growing epitaxy layers of the firstlight-emitting elements 101. In an embodiment, the tenth substrate 901has sapphire, silicon, germanium, or nitride. In an embodiment, theadhesive structure 50 is arranged between the first and second electrodepads 120,121 and the eleventh substrate 902.

Referring to FIG. 4B, a part of the tenth substrate 901 is removed toform a thinned substrate 9010. The thinned substrate 9010 has athickness less than that of the tenth substrate 901. In an embodiment,the thickness of the thinned substrate 9010 is between 10 μm˜50 μm.

Referring to FIG. 4C, the thinned substrate 9010 is divided into severalunit substrates 901 a, 901 b, 901 c. The unit substrates 901 a, 901 b,901 c are connected to different first light-emitting elements 101respectively. For example, the unit substrate 901 a is connected to thefirst light-emitting element 101 a, the unit substrate 901 b isconnected to the first light-emitting element 101 b, and the unitsubstrate 901 c is connected to the first light-emitting element 101 c.The process of forming the unit substrates 901 a, 901 b, 901 c can beperformed by using a dicing blade or a laser having a wavelength between260 nm and 380 nm. During forming multiple unit substrates 901 a, 901 b,901 c, the first light-emitting elements 101 and the eleventh substrate902 are not damaged, but a portion of the adhesive structure 50 isremoved. The unit substrate 901 a, 901 b, 901 c has a width narrowerthan that of the thinned substrate 9010, and one unit substrate 901 a,901 b, 901 c corresponds to or covers only one first light-emittingelement 101. In an embodiment, one unit substrate 901 a, 901 b, 901 ccorresponds to or covers two or more first light-emitting element 101.

Referring to FIG. 4D, a twelfth substrate 903 covered by an intermediatelayer 3 is provided. The twelfth substrate 903 has a twelfth lowersurface 9030 and a twelfth upper surface 9031. The intermediate layer 3is arranged on the twelfth lower surface 9030. The unit substrates 901a, 901 b, 901 c are connected to the twelfth substrate 903 through theintermediate layer 3. In another aspect, the first light-emittingelement 101 and corresponding unit substrate 901 a, 901 b, 901 c areconnected to the twelfth substrate 903 through the intermediate layer 3.

Referring to FIG. 4E, the eleventh substrate 902 is removed to exposethe first light-emitting elements 101. The bottom surface 1011 and thefirst and second electrode pads 120, 121 of the first light-emittingelements 101 are exposed. All or a part of the adhesive structure 50 canbe removed before or after removing the eleventh substrate 902. In anembodiment, a portion of the adhesive structure 50 is left on the firstlight-emitting element 101 and/or the unit substrates 901 a, 901 b, 901c after removing the eleventh substrate 902. In an embodiment, a portionof the adhesive structure 50 is left on the first and second electrodepads 120, 121 after removing the eleventh substrate 902.

Referring to FIG. 4F, a thirteenth substrate 904 is arranged under thetwelfth substrate 903. The thirteenth substrate 904 has a thirteenthlower surface 9041 and a thirteenth upper surface 9040. The connectingpads 104 are arranged on the thirteenth upper surface 9040. Theconnecting pads 104 are arranged on the thirteenth upper surface 9040,and a part of the thirteenth upper surface 9040 is exposed without beingcovered by the connecting pads 104. Then, the protrusions 30 are formedto push the first light-emitting elements 101 to the thirteenthsubstrate 904. For example, the first light-emitting elements 101 a, 101b, 101 c are pushed away from the twelfth substrate 903 by theprotrusions 30, and the first light-emitting elements 101 a, 101 b, 101c are then fixed to the thirteenth substrate 904 to form alight-emitting device 4000 shown in FIG. 4G. Referring to FIG. 4F, alaser is applied to form the protrusions 30. In an embodiment, thetwelfth substrate 903 has a transmittance over 90% or a reflectance lessthan 10% with respect to the laser so the laser can pass through thetwelfth substrate 903. The descriptions about laser can be referred toprevious paragraphs. In an embodiment, a spacer is arranged between thetwelfth substrate 903 and the thirteenth substrate 904 to keep the firstlight-emitting elements 101 from directly contacting with the thirteenthsubstrate 904 before leaving the twelfth substrate 903. Descriptionabout the spacer can be referred to previous paragraphs and paragraphscorresponding to FIGS. 6A˜6C, and is omitted for brevity.

Referring to FIG. 4G, the light-emitting device 4000 has the firstlight-emitting elements 101 (for example, the first light-emittingelements 101 a, 101 b, 101 c), the thirteenth substrate 904, the unitsubstrates 901 a, 901 b, 901 c, and the connecting pads 104. The firstlight-emitting elements 101 are connected to the unit substrates 901 a,901 b, 901 c. For example, the first light-emitting element 101 a isconnected to the unit substrate 901 a, the first light-emitting element101 b is connected to the unit substrate 901 b, and the firstlight-emitting element 101 c is connected to the unit substrate 901 c.The unit substrate 901 a has a top surface 90100 a parallel to thethirteenth upper surface 9040 and an inclined surface 90100 b notparallel to the thirteenth upper surface 9040. The light from the firstlight-emitting element 101 leaves the unit substrate 901 a from theinclined surface 90100 b to increase the luminous intensity and improvethe uniformity of the light field provided by the light-emitting device4000.

In an embodiment, conductive wires, active electronic elements and/orpassive electronic elements are arranged on the thirteenth upper surface9040 and/or on the thirteenth lower surface 9041. For example, referringto FIG. 4G, the first light-emitting elements 101 a, 101 b, 101 c in thelight-emitting device 4000 are electrically connected to the conductivewires (not shown) on the thirteenth upper surface 9040. Thelight-emitting device 4000 can receive power and control signals throughthe conductive wires (not shown) for transmitting the power and controlsignals to control the first light-emitting elements 101 a, 101 b, 101 ctogether or separately. In an embodiment, the connecting pads 104 arearranged on the thirteenth upper surface 9040 with a predetermineddistance, and the first light-emitting elements 101 are placed on theconnecting pads 104 according to the predetermined distance.Descriptions about the conductive wires, active electronic elements andpassive electronic elements can be referred to previous paragraphs.

In addition, one or more distance adjusting substrates and relatedprocess can be incorporated to the manufacturing process to change thedistance between two neighboring first light-emitting elements 101 inthe light-emitting device 4000. The distance adjusting substrate can bestretched in one dimensional direction or in two dimensional directionsto change the distance between light-emitting elements arranged thereon.For example, a first distance adjusting substrate and related process isperformed after the process shown in FIG. 4E. Referring to FIG. 4E, thefirst distance adjusting substrate is provided to be attached to thefirst light-emitting element 101 from the side opposite to the twelfthsubstrate 903. Next, the twelfth substrate 903 is removed and the firstlight-emitting elements 101 and corresponding unit substrates 901 a, 901b, 901 c on the twelfth substrate 903 are transferred to the firstdistance adjusting substrate, wherein the first light-emitting elements101 are directly in contacted with the first distance adjustingsubstrate and the corresponding unit substrates 901 a, 901 b, 901 c areexposed. After transferring the first light-emitting element 101 andcorresponding unit substrates 901 a, 901 b, 901 c to the first distanceadjusting substrate, the first distance adjusting substrate is stretchedto increase the distance between two first light-emitting elements 101.The first distance adjusting substrate can be stretched in onedimensional direction or in two dimensional directions so the distancebetween two first light-emitting elements 101 in one dimensionaldirection or in two dimensional directions can be increased. Afterstretching the first distance adjusting substrate, a second distanceadjusting substrate is provided to transfer first light-emittingelements 101 by directly connecting the unit substrates 901 a, 901 b,901 c and the second distance adjusting substrate, and the firstdistance adjusting substrate is then removed. After transferring thefirst light-emitting elements 101 and corresponding unit substrates 901a, 901 b, 901 c to the second distance adjusting substrate, pushing thesecond distance adjusting substrate toward the thirteenth substrate 904to connect the first light-emitting elements 101 and the thirteenthupper surface 9040 and removing the second distance adjusting substrateto form the light-emitting device 4000. The distance adjusting substratecan be a blue tape and has an area same as or different from that of thetwelfth substrate 903. Moreover, in an embodiment, the substrate 201,202, 203, 204, 701, 702, 703, 704, 705, 902, 903, 904 can be stretchedin one dimensional direction or in two dimensional directions to changethe distance in one dimensional direction or the distances in twodimensional directions between the light-emitting elements arrangedthereon.

Referring to the process shown in FIGS. 3A˜3C, a relative positionadjusting substrate can be incorporated in the process in FIGS. 4A˜4G toadjust the relative position of the first light-emitting elements 101 onthe thirteenth substrate 904. For example, a relative position adjustingsubstrate is provided, and the first light-emitting elements 101 in FIG.4E are connected to the relative position adjusting substrate. Next, thetwelfth substrate 903 is removed to expose the unit substrates 901 a,901 b, 901 c. Then, the first light-emitting elements 101 and the unitsubstrates 901 a, 901 b, 901 c are pushed to the thirteenth substrate904. Therefore, the first light-emitting elements 101 are connected tothe thirteenth substrate 904 through the unit substrates 901 a, 901 b,901 c. Then, wires are provided to connect the first and secondelectrode pads 120, 121 and the connecting pads 104 to form alight-emitting device. In an embodiment, the relative position adjustingsubstrate is a blue tape.

FIGS. 5A˜5G show schematic views protrusion and adhesive unit inaccordance with one embodiment of the present disclosure. Referring toFIG. 5A, two protrusions 30A, 30B push the first light-emitting element101 away from the intermediate layer 3, causing the first light-emittingelement 101 to fly to the adhesive unit 5. Referring to FIG. 5B, theprotrusions 30 push the first light-emitting elements 101 a, 101 b awayfrom the intermediate layer 3, causing the first light-emitting elements101 a, 101 b to fly to the adhesive units 5 a, 5 b. Referring to FIG.5C, the protrusions 30A, 30B, 30C push the first light-emitting elements101 a, 101 b away from the intermediate layer 3, causing the firstlight-emitting elements 101 a, 101 b to fly to the adhesive units 5 a, 5b. The first light-emitting element 101 pushed by the protrusion 30 canbe connected to different adhesive units 5. Referring to FIG. 5D, thefirst light-emitting element 101 is pushed to the adhesive units 5 a, 5b by the protrusion 30. The first electrode pad 120 of the firstlight-emitting element 101 is connected to the adhesive unit 5 acovering the connecting pad 104 a. The second electrode pad 121 of thefirst light-emitting element 101 is connected to the adhesive unit 5 bcovering the connecting pad 104 b. Referring to FIG. 5E, the firstlight-emitting element 101 is pushed to the adhesive units 5 a, 5 b bythe protrusions 30A, 30B. Referring to FIG. 5F, the first light-emittingelement 101 a is pushed to the adhesive units 5 a, 5 b by the protrusion30, and the first light-emitting element 101 b is pushed to the adhesiveunits 5 c, 5 d by the protrusion 30. Referring to FIG. 5G, the firstlight-emitting elements 101 a, 101 b are pushed to the adhesive units5a, 5 b, 5 c, 5 d by the protrusions 30A, 30B, 30C. In an embodiment,the protrusion 30 does not push the first light-emitting element 101away from the intermediate layer 3, but can be expanded to a height suchthat the first light-emitting element 101 directly contacts the adhesiveunit 5. That is, the first light-emitting element 101 can simultaneouslycontact the adhesive unit 5 and the protrusion 30 during the transferprocess.

FIGS. 6A˜6C show schematic views of spacer and substrate in accordancewith one embodiment of the present disclosure. For the convenience ofdescription, only the substrate and the spacer are marked, and thelight-emitting element, the connecting portion and the adhesive unit arenot indicated in FIGS. 6A˜6C. Referring to FIG. 6A, the spacers 61 a, 61b, 62 a, 62 b are positioned on the corners 202 a, 202 b, 202 c, 202 dof the second substrate 202. In an embodiment, the spacer can be placedat the areas other than the corner of the substrate. Referring to FIG.6B, the spacers 63 a, 63 b, 63 c, 63 d are arranged near the edge sides202 ab, 202 ac, 202 cd, 202 bd, and the spacers are not arranged on thecorners 202 a, 202 b, 202 c, 202 d. In an embodiment, the spacer can beplaced around the geometrical center of the substrate. Referring to FIG.6C, the spacers 64 a, 64 b, 64 c, 64 d surround the geometrical center Cof the second substrate 202 in a top view. The arrangement of thespacers is not limited to the patterns shown in FIGS. 6A˜6C, and thepatterns in FIGS.6A˜6C can be combined. For example, the patterns inFIGS. 6A, 6C are combined, and the spacers can be arranged on thecorners and around the geometrical center of the substrate. Or, thepatterns in FIGS. 6A, 6B are combined, and the spacers can be arrangedon the corners and edge portions of the substrate. Or, the patterns inFIGS. 6B, 6C are combined, and the spacers can be arranged around thegeometrical center of the substrate and edge portions of the substrate.

The manufacturing process disclosed in FIGS. 1A˜1C, 2A˜2C, 3A˜3C, 4A˜4Gcan incorporate the embodiment disclosed in FIGS. 5A˜5G. That is, one ormore protrusions 30 can be formed to push one or more firstlight-emitting elements 101 at once in the above manufacturingprocesses. One adhesive unit 5 can be formed to cover one or moreconnecting pads 104. One first light-emitting element 101 can beconnected to one or more adhesive units 5.

The foregoing description has been directed to the specific embodimentsof this disclosure. It will be apparent to those having ordinary skillin the art that other alternatives and modifications can be made to thedevices in accordance with the present disclosure without departing fromthe scope or spirit of the disclosure. In view of the foregoing, it isintended that the present disclosure covers modifications and variationsof this disclosure provided they fall within the scope of the followingclaims and their equivalents.

What is claimed is:
 1. A method of manufacturing a light-emittingdevice, comprising: providing a first substrate; forming a firstadhesive unit on the first substrate; forming a first light-emittingelement on the first substrate; providing a second substrate; forming asecond light-emitting element on the second substrate; forming a thirdlight-emitting element on the second substrate; and connecting thesecond light-emitting element to the first adhesive unit, wherein thethird light-emitting element is overlapped with the first light-emittingelement during connecting the second light-emitting element to the firstadhesive unit.
 2. The method of claim 1, further comprising forming aconnecting pad on the first substrate, wherein the connecting pad isarranged between the first adhesive unit and the first substrate.
 3. Themethod of claim 1, further comprising forming a second adhesive unit onthe first substrate, wherein the second adhesive unit is connected tothe first light-emitting element.
 4. The method of claim 1, furthercomprising forming an intermediate layer on the second substrate,wherein the second substrate is arranged between the secondlight-emitting element and the second substrate.
 5. The method of claim4, wherein the intermediate layer is connected to the thirdlight-emitting element.
 6. The method of claim 4, further comprisingforming a protrusion on the intermediate layer to push the secondlight-emitting element toward the first adhesive unit.
 7. The method ofclaim 1, wherein the first light-emitting element emits a light having afirst peak wavelength and the second light-emitting element emits alight having a second peak wavelength different from the first peakwavelength.
 8. The method of claim 1, further comprising forming asecond adhesive unit on the first substrate.
 9. The method of claim 1,further comprising forming a spacer between the first substrate and thesecond substrate.
 10. The method of claim 1, wherein the first adhesiveunit comprises insulating material and conductive particles.
 11. Amethod of manufacturing a light-emitting device, comprising: providing afirst substrate; forming a first adhesive unit on the first substrate;forming a first light-emitting element on the first substrate; providinga second substrate comprising an intermediate layer; forming a secondlight-emitting element on the second substrate; forming a firstprotrusion to push the second light-emitting element toward the firstsubstrate; and connecting the second light-emitting element to the firstadhesive unit.
 12. The method of claim 11, further comprising forming aconnecting pad on the first substrate, wherein the connecting pad iscovered by the first adhesive unit.
 13. The method of claim 11, furthercomprising forming a second adhesive unit on the first substrate. 14.The method of claim 11, further comprising forming a second protrusionto push the second light-emitting element toward the first substrate.15. The method of claim 11, further comprising forming a thirdlight-emitting element on the second substrate.
 16. The method of claim15, wherein the third light-emitting element is pushed toward the firstsubstrate by the first protrusion.
 17. The method of claim 15, furthercomprising forming a second protrusion to push the second light-emittingelement and the third light-emitting element toward the first substrate.18. A method of manufacturing a light-emitting device, comprising:providing a first substrate comprising; forming a first adhesive unitand a second adhesive unit on the first substrate; forming a firstlight-emitting element on the first substrate; providing a secondsubstrate; forming a second light-emitting element on the secondsubstrate; forming a first protrusion to push the second light-emittingelement toward the first substrate; and connecting the secondlight-emitting element to the first adhesive unit and the secondadhesive unit.
 19. The method of claim 18, further comprising forming asecond protrusion to push the second light-emitting element toward thefirst substrate.
 20. The method of claim 18, further comprisingproviding a first connecting pad and a second connecting pad on thefirst substrate, wherein the first connecting pad is covered by thefirst adhesive unit and the second connecting pad is covered by thesecond adhesive unit.